<!DOCTYPE html>
<div style="width: 200px; height: 200px; background-color: lightgreen"></div>
<div style="position: relative; top: -50px; left: 50px; width: 200px; height: 200px; background-color: blue">
    <div id="child" style="background-color: green; width: 100px; height: 100px;"></div>
</div>
